TM 5-6115-434-122-23. Operation in Muda.The power unit will operate satisfactorily in mud provided sufficient support is provided the skids from sinking tothe point that mud blocks the various fuel and moisture drains in the bottom of the enclosure.b.The power unit should be inspected frequently to insure that mud has not plugged any drains, fittings or otheropenings.c.Boards or other suitable support material should be placed around the power unit to provide solid, dry surfacesfor personnel operating and servicing the power unit.2-24. Operation at High AltitudesThe power unit will operate satisfactorily at altitudes up to 10,000 feet.2-25. Operation Below Sea LevelThe power unit will operate satisfactorily below sea level.Section VI. OPERATION OF AUXILIARY MATERIAL USED IN CONJUNCTION WITH THE EQUIPMENT2-26. GeneralThe power unit is equipped with a 2 ¾ pound dry charge fire extinguisher, bracket mounted on the remote powerconnection panel (fig. 2-3). The extinguisher, charged with purple-K dry chemical, is suitable for all type fires. Asqueeze of the trigger breaks the seal disc in the top of the pressurized dry chemical shell and starts the discharge.When trigger is released, discharge stops, permitting intermittent discharge. Once seal disc is broken, valve will holdpressure in shell only for a few hours. After using, replace with a new shell immediately.2-27. Fire Extinguishera.Use.To use the fire extinguisher, point the nozzle at the base of the flame and squeeze trigger. Apply chemicaluntil all signs of fire have been extinguished.b.Recharging.Recharge immediately after using. Squeeze trigger to vent pressure. Unscrew and discard usedshell. Remove dry chemical remaining in head. Insert new indicator tab into trigger. Screw new shell firmly into head.Insert new indicator tab into control head.c.Maintenance.Semiannually, unscrew shell from head. Be sure trigger works freely and nozzle is clean. Followmaintenance instructions on shell. Insert new indicator into trigger. Screw shell firmly into head. Insert new indicatorinto control head.2-56